Improvement in ventilators for railway cars



. THOMAS w. renuncian, on

PATENT OFFICE.

NEWPORT, RHODE ISLAND.

IMPROVEMENT IN VENTlLAI'ORS FOR RAILWAY CARS.

Specification formingr part of Letters Patent No. 126,797, dated May 14,1872.

ventilator, and to prevent the wind from driving down and making a backdraught.l The nature of my invention and the manner in which the same isor may be carried into effect can best be explained and understood byreference to the accompanying-drawing, in which- Figure 1 is aperspective view of a ventilator made in accordance with my invention.

Fig.2 is a vertical central section of the saine on an enlarged scale.

A represents the ventilator-shaft or pipe which enters the body of thecar. Upon the upper end of this pipe is affixed'the enlarged bulginghead B, by means of which and the appliances hereinafter described theupward draught is assured and back draught is prevented. The head B inthis instance consists of two conical frustums, a b, with their basesput together, the inverted smaller end of the lower frustum a beingattached to the pipe A. The sides of the .lower frnstum are providedwith a series of downwardly-projectin g tubes, o, through which airpasses from the outside into the head B. These pipes are of any desirednumber; on a ventilator of ordinary size I have found that six willanswer, placed around the head vat equal intervals apart. They will takethe air from any direction, causing a powerful up draught through theventilator, while they are arranged at such an angle as to prevent thewind from driving down and making a back draught. I have found that forthis purpose it will answer to Vplace them at an angle of aboutforty-five degrees from the perpendicular. The outlet at the top of thehead B should have about the same diameter as that of thepipe A in orderto insure a more perfect delivery or escape of the air, smoke, &c.,passing up through the ventilator. Over the top of the head is placed aconical cap, C, which should extend down sufficiently far over the sidesof the upper part b of the head as to prevent any down draught throughthe head, and which at its base is of sufficient diameter to leavebetween it and the head an annular passage of such dimensions as willpermit the free escape of the air, smoke, &c., passing up through theventilator. A plate, d, is placed inside of the cap at a suitabledistance above the outlet of the head in order to prevent accumulationof air or smoke above that point in the cap C. The cap'is supported inits proper position above the head by means of legs e or other suitablemeans.

By means of the pitched top or cap C and the inclined inlet-tubes B,arranged as shown, any down draught or passage downward of air taken inthrough the ventilator-head is pre- Vented, and an upward draught iscreated, which is very powerful and elfective. In order, however, toobtain an even better delivery of the foul air, smoke, &c., accumulatedby the artificial draught created by the inlet-pipes, I form in thesides of the upper frustum b of the head outlet apertures, f,which onthe exterior are covered by hoods g, extending down over and below saidoutlet apertures or openings sufficiently far to prevent. air from theoutside entering said apertures and driving downward, so as toneutralize more or less the up draught created by the pipes B. In thisway the action of the ventilator is rendered even more effective thanwith the top or cap lC alone. The direction of the dr( ught and the operation of the ventilator are indicated by the arrows, and require nofurther explanation.

The parts of the ventilator may be made of any suitable material and canbe of varied proportions relatively to each other. I will, however,indicate the proportionswhich I have found to be well adapted for aneight-inch ventilator, the same proportions being equally well adaptedfor other sizes. When the pipe A is eight inches in diameter, Iproportion the other .parts as follows: The axial length of frustum a,eight inches; axial length ofl frustum b, six inches; diameter of basesof a and b, sixteen inches; diameter of outlet and bottom openings ofthe head B, eight inches; tubes c, four inches long and two inches indiameter; openings f, two inches in diameter,

hoods g, four inches long; cap O, twelve inches in drop and i'teeninches in diameter at the base; plate d, eight inches in diameter andtwo inches above the outlet or top of the head B.

A ventilator made as above described is cheap, easily made, and mostei'ective in operation, having none of the objectionable feat ures ofother ventilators now in use.

What I claim, and desire to secure by Letters Patent, is

l. The combination, with the exhaust or eduction pipe and theventilator-head composed of two conical frustums, as herein described,of the inclined draught-tubes in the lower frustum and the conical capover the top of the upper frustum, all constructed and arranged forjoint operation as herein shown and set forth.A

2. In combination with the elements speciied in the preceding clause,the hooded discharge-apertures arranged in the upper frustum of thehead,as shown and described.

In testimony whereof I have have signed my name to this specilicationbefore two subscribin g witnesses. y

- THOMAS W. FREEBORN.

Witnesses:

STEPHEN GoULD, WM. (l. CoZZENs, Jr.

